Since late 2010, Green Power, Friends of Sai Kung and the Eco-Education and Resources Centre have been conducting surveys at 28 enclaves not included in country parks, to assess their ecological value and reveal possible threats from development. In addition to the earlier discovery of illegal development at Pak Lap and plans for luxury housing at Wong Chuk Yeung, Sai Kung, we recently found that a large area at Pak Sha O enclave had been destroyed. We are worried that such large-scale wetland destruction has already affected the area’s unique ecology.
Pak Sha O, near Hoi Ha, Sai Kung, is a large freshwater wetland and stream habitat, with a total area of 29 ha. It is surrounded by Sai Kung West Country Park but has not been included in any statutory planning. An old Hakka village, Pak Sha O was settled by the Ho clan that immigrated from Shenzhen in 1911. By the end of the 1970s, most of the Ho clan had emigrated. In 1980, several expatriates, of about seven households, rented and moved in to village houses. On 10 November 2010, the Entrance Hall, Watchtower and Side Chamber of the Ho Residence, Ho Ancestral Hall and Side Rooms on Two Sides of the Ho Ancestral Hall were listed as Grade I historic buildings in Hong Kong.
Large-scale excavation work by several diggers was discovered in the area. Some 3000sq m of wetland was affected. We investigated at the Lands Department and found that most of the farmlands had been sold to different developers. We suspected that agricultural activity was used as a smokescreen to "destroy first, develop later" in order to exploit the wetland. After the large scale excavation work and river diversion at Pak Sha O, the hydrology and species diversity will be severely damaged. Wetland ecology may not recover. A developer may consider this beneficial, as it may make it far easier to succeed in applying to the Lands Department for re-classing land use to enable development.
The large-scale excavation may have already caused irreversible damage to the area’s wetland ecology. According to our surveys, Pak Sha O enclave has high biodiversity, including 75 butterfly species which is close to 30% of the total butterfly species recorded in Hong Kong, which means it can be classed as a butterfly hotspot. For example, Constable (Dichorragia nesimachus), Chestnut Bob (Iambrix salsala), Lesser Forest Blue (Taraka Hamada) and White Dragontail (Lamproptera curius) are locally "Rare" or "Very Rare" species. We also recorded 11 freshwater fish species, including Hong Kong’s second record of Three-lines Bagrid Fish (Pseudobagrus trilineatus), which is listed as "Vulnerable" on the China Species Red List. We also recorded 38 bird species, including Eagle Owl (Bubo Bubo), Crested Serpent Eagle (Spilornis cheela) and Asian Paradise Flycatcher (Terpsiphone paradisi), of which Eagle Owl and Asian Paradise Flycatcher are scarce in Hong Kong, and Chinese Goshawk (Accipiter soloensis) and Crested Serpent Eagle (Spilornis cheela) are uncommon. We also found 8 amphibian and 23 reptile species, among which Reeve's Turtle (Chinemys reevesii) is classified as "Endangered" whereas King Cobra (Ophiophagus Hannah) and Burmese Python (Python bivittatus) are classified as "Vulnerable" in the IUCN Red List of Threatened Species.
Pak Sha O has been a shining example of how biodiversity, culture and humanity can exist and remain in harmony in Hong Kong. However it is now under immense development pressure. We urge the government to include the enclave in the country park area or even designate the area as a Site of Special Scientific Interest as soon as possible, to prevent further damage.